Post-doctoral researcher position: Analysis of fundamental electronic properties of nitride-based heterostructures and light emitting devices

Tyndall National Institute at University College Cork invites applications for a postdoctoral researcher position. The research is theory-driven, spanning basic science through to investigations of fundamental processes limiting present day devices, and including design and modeling of new and optimized devices.

Overall the project will develop a fundamental understanding of non-radiative carrier recombination and transport properties of disordered semiconductors. It shall also lead to the development of strategies to minimise the deleterious effect of non-radiative recombination processes in important and future photonic devices.

Quantum wells based on the III-N alloy InGaN offer enormous potential for use in such diverse areas as solid-state lighting and large area displays. Despite substantial progress, several key issues in nitride-based light emitting diodes still exist and need to be addressed to unveil their full potential. One key issue is the so-called efficiency “droop”, describing the effect that the device efficiency reduces significantly with increased drive current. The central aim of the project is to provide insight into the question surrounding the “droop” by atomistic calculations for realistically sized nitride-based InGaN quantum wells plus developing simpler models to capture the main features of atomistic calculations. Here, we are interested in both understanding basic properties and how these impact the device performance. The aims of this project are therefore to

1. investigate and understand the impact of alloy fluctuations, built-in field, and well width fluctuations on non-radiative recombination processes in InGaN-based quantum wells;
2. investigate and understand the impact of carrier localization on transport properties in InGaN-based structures;
3. Develop simplified models, building on semi-empricial atomistic approaches, to treat carrier localization effects and non-radiative processes;
4. use the understanding gained to guide design of III-N devices with improved properties/characteristics.

The project targets a close linkage between theory and experiment, to elucidate how to manage carrier transport and non-radiative recombination processes in future photonic materials and devices in general.

Responsibilities

• Analysis of nitride-based LED structures, including carrier transport, radiative and non-radiative recombination processes
• Development of carrier transport codes, accounting for alloy fluctuations and related carrier localization effects in the active region and the barrier material of InGaN-based multi quantum well systems.
• Close interaction with experimental partners and guidance of device design.
• Engage in the dissemination of the results of the research, as directed.
• Engage in the wider research and scholarly activities of the research group.
• Interact closely with postgraduate research students in support of their research in conjunction with an academic supervisor.

Requirements

The successful candidate for the positions will

• have recently completed a PhD degree in physics, electrical engineering, applied mathematics, chemistry or materials science.
• have an appropriate technical competence and accomplishment.
• have a very strong ability/expertise in code development.
• be highly self-motivated and able to demonstrate initiative.
• have a capability of working within a project team to achieve results.
• have very good communication, organisation and interpersonal skills.

Desirable

Knowledge of one or more of the following

• continuum-based drift-diffusion transport solver.
• non-equilibrium Green’s function transport calculations.
• photonic device simulations.
• finite-element or finite-difference methods.

Informal enquiries concerning this position can be made to: Dr. Stefan Schulz (email [email protected]).

Please apply via http://www.tyndall.ie/career/search, selecting reference number SS-4 and following the instructions to complete the associated application form, attaching your CV and motivation letter.